Charge-Coupled Devices are in widespread commercial use and are well understood. A CCD is comprised of a semiconductor substrate in which rows and columns of light sensitive cells (pixels) are defined by photolithographic masking, deposition and diffusion steps. The device includes an overlying multi-phase gate electrode structure operative in response to gate drivers activated by digital clock pulses. In response to the drive pulses, a pattern of charges representative of a light image impinging on the surface of the device, is transferred in parallel rows along columns to a, usually masked, serial register from which successive rows of charges are transferred to an output charge sensitive amplifier for processing. CCDs have utility in television, medical imaging, and a variety of analytical instrument applications including spectroscopy, electrophoresis, electron microscopy, and light microscopy.